ip = int(input())

if ip >= 30:
    print("Yes")
else:
    print("No") ip = int(input()) ip int(input()) int input() input if ip >= 30:
    print("Yes")
else:
    print("No") ip >= 30 ip 30 print("Yes") print "Yes" print("No") print "No" ip = int(input()) int(input()) ip
ip = int(input())

if ip >= 30:
    print("Yes")
else:
    print("No")
